For a conventional controller-integrated rotary electric machine in which a control unit is coaxially integrated with a rotary electric machine driven by a command from the control unit, in order to couple the rotary electric machine to a control unit portion, a structure in which protruding portions provided on their peripheries are connected by screws has been proposed.
However, the controller-integrated rotary electric machine in which the control unit and the rotary electric machine are coupled by the screwing structure needs the protruding portions for the screws, which makes the layout difficult and causes a drawback in downsizing.
Furthermore, in order to couple the rotary electric machine to the control unit portion, what is called a shrink fitting structure and method for coupling two objects using thermal expansion and shrinkage has been proposed. However, the shrink fitting structure needs a complicated process and also needs a countermeasure against heat. Furthermore, for welding, if both the control unit portion and the rotary electric machine are made of a ferrous metal, they can be welded, but, if one or both of them are made of a metal with good heat conductivity, such as aluminum, welding is difficult. In addition, high heat is applied, although locally, a countermeasure against heat is needed for electronics components and the like in the control unit portion.
Still furthermore, welding, swaging and the like are also used as a structure and method for coupling the rotary electric machine to the control unit portion. For a swaged structure, an exterior yoke on the rotary electric machine side is extended along the axial-length direction, then an edge of the extended yoke is bent into a groove provided in the outer periphery on the control unit side and swaged, thereby coupling the rotary electric machine to the control unit. In a conventional swaged structure, a yoke of an electromagnetic drive unit portion is extended, the extended portion being thin cylindrical, then the tip of the extended portion is bent in an L-shape or obliquely into one face of a stationary core to be swaged across the whole circumference (e.g., see PTL 1).